Apparatus and methods are known for accessing a patient's vasculature percutaneously for performing a procedure within the vasculature. For example, a hollow needle may be inserted through a patient's skin and overlying tissue into a blood vessel. A guidewire is then passed through the needle into the blood vessel, whereupon the needle is removed. An introducer sheath is then advanced over the guidewire into the vessel, e.g., in conjunction with or subsequent to one or more dilators. A catheter or other device may be advanced through the introducer sheath and over the guidewire into a position for performing a medical procedure within the patient's body. In this manner, the introducer sheath facilitates introducing various instruments into the vessel, while minimizing trauma to the vessel wall and blood loss.
Upon completing the procedure, the instrument(s) and introducer sheath are removed, leaving a puncture extending between the skin and the vessel. To seal the puncture, external pressure may be applied to the overlying tissue, e.g., manually and/or using sandbags, until hemostasis occurs. This procedure, however, can be time consuming and expensive, requiring as much as an hour of a medical professional's time. It is also uncomfortable for the patient, and may require the patient to remain immobilized in an operating room, catheter lab, or holding area. In addition, a risk of hematoma exists from bleeding before hemostasis occurs.
Various apparatus and methods have been suggested for sealing a percutaneous puncture instead of or in addition to using external pressure. For example, U.S. Pat. No. 5,108,421 to Fowler discloses using a collagen plug that is delivered into a puncture through tissue. After completing the procedure, the introducer sheath and/or guidewire used to access the patient's vasculature via the puncture are removed. In one embodiment, a catheter is inserted through the puncture into the blood vessel. A balloon on the catheter is expanded and then retracted until the balloon is disposed adjacent the puncture at the wall of the vessel. A plug is then advanced into the puncture until the plug contacts the balloon, thereby preventing the plug from entering the vessel. Once the plug is positioned within the puncture, the balloon is deflated and withdrawn, leaving the plug to expand and seal the puncture and/or promote hemostasis.
By way of another example, U.S. Pat. Nos. 5,192,302 and 5,222,974 issued to Kensey et al. describe using a collagen plug that may be delivered through an introducer sheath into a puncture site.
Such sealing methods generally involve introducing plugs or other materials into the puncture after completing the procedure and removing the introducer sheath. With the introducer sheath removed, there is substantial risk of hematoma within the tissue surrounding the puncture as blood from the vessel leaks into the puncture, which may be uncomfortable and/or harmful to the patient. Further, temporary hemostasis devices for isolating the vessel from the puncture may be difficult to use effectively and/or may be expensive. Despite attempts to isolate the vessel from the puncture while delivering a plug or other sealing material, the sealing material may still leak and/or become exposed in the vessel, where the sealing material may risk causing an embolism in the vessel.